Recently, hydrogen has attracted attention as an energy source for a wide variety of industrial and scientific uses, in particular, as a clean fuel substitute for fossil fuel. Because hydrogen is an extremely flammable and explosive gas, hydrogen sensors must be employed to monitor the environment where hydrogen is utilized. This can not only safeguard the apparatus and associated operating personnel, but can also ensure the efficiency and operational integrity of the hydrogen powered apparatus. Hydrogen sensors, for example, for use with coal-derived gas and hydrogen fuel cells, require low power consumption and a short response time in the range of 1-2 seconds
Conventional hydrogen sensors, however, use high operating bias voltage which requires high power levels. Another drawback of conventional hydrogen sensors is that they monitor the conductivity change of the sensing element upon exposure to the hydrogen. This results in detection times typically in the range of minutes at room-temperature. A conventional solution for decreasing the response time is to heat up the sensing element. However, this adds weight and dramatically increases the power requirements of the sensor. In addition, conventional hydrogen sensors trigger a detection signal simply by sounding-off an alarm. In some cases, it may be desirable to send indication of detection to a remote location and/or to locations out of hearing range of the alarm.
Thus, there is a need to overcome these and other problems of the prior art and to provide a system for hydrogen sensing with low power consumption, fast response, and signal transmission to a remote location. It is further desirable to provide a system that can operate by harvesting energy.